The known washing machines currently in use and in prior art literature usually comprise a shell, an inner cylinder or tub, a prime mover and an impeller which is either a multi-bladed propeller installed at the lower recessed side of the tube or an elongated four-cornered piece installed vertically at the center of the tub. In the former, tangential flow of the water is effected with the section directly in the path of the current attaining maximum cleaning process while the rest considerably less. Moreover, uni-directional flow results thereby decreasing the relative velocity of solid materials and the soap solution lessening further its cleaning efficiency. Obviously, the overall efficiency of such a unit is low with characteristically uneven cleaning. In the latter, wherein the agitator is installed at the center of the tub, it is fairly obvious that the effective volume where the cleaning process occur is reduced. Again, the effectivity of the washing process is concentrated in that area immediately surrounding the agitator with the outermost section having the least efficiency. With the agitator so located it will not be practical to utilize the unit for cleaning dinner wares as the chances for breakage are quite apparent. Compounding these inherent defects is the fact that in almost all the models cited the power shaft actuating the propeller or agitator penetrates the tub which will therefore require sealing to prevent leaks which will certainly hasten the deterioration of the parts and causing damage to the motor. As can be observed, in actual cases, these destructive events occur in most models because of the failure of the seal.
Due to their peculiar construction, strong materials, such as stainless steel, are used for the tub and mild steel plate with enamel paint finish for the shell. The impeller is made of hard rubber. All these add immersely to the cost of the machine.
The aforementioned disadvantages are eliminated by the present invention wherein the power shaft does not penetrate the bottom wall of the tub to actuate the agitator. Rather, the link-up with the agitator is effected by a yoke-like structure connected at its base to a rotatively oscillating shaft while its two vertically extending arms are bent 180 degrees to enter the tub at its upper end on opposite points and connect with the agitator. Sealing is thus dispensed with. This condition is made possible by the unique design and construction of the agitator. Briefly stated, the agitator is similar to a widely spaced, involutely and internally serrated cylinder dimensioned to leave adequate clearance with the inner wall of the tub. As it oscillates rotatively, each serration propels a jet of water toward the center of the tub with a direction opposite that of the fabric material. High relative velocity between the former and the latter is thus assured favoring, in turn, high cleansing efficiency. In addition to these, even distribution of the effective washing volume to practically the entire tub results aside from making the effective washing volume of the tub itself comparatively larger owing to the peripherally located agitator. Moreover, this unique design enables one to safely and effectively wash dinner wares as the danger of breakage is nil. Further, the construction itself does not require strong materials. Hence, light materials such as fiberglass may be used for the shell, the tub and the agitator making the machine not only cheap but also corrosion-free. Further, the bearings and the rubbing surfaces are located in a closed compartment provided with lubricating material.
It is therefore the principal object of this invention to provide a washing machine with an agitator peripherally located inside the tub.
Another object of this invention is to provide a washing machine with a leakproof tub.
A further object of this invention is to provide a washing machine which evenly distributes the effective washing volume throughout the tub.
Another object of this invention is to provide a washing machine with a comparatively large effective washing volume of the tub.
Another object of this invention is to provide a dual purpose washing machine, capable of washing both dinner wares and fabrics.
A further object of this invention is to provide a washing machine that is simply constructed and utilizing light materials, cheap and effective.
Another object of this invention is to provide a washing machine that is portable, highly efficient with rubbing surfaces constantly and adequately lubricated.